This invention relates to expendable immersion devices of the type which are inserted into a bath of molten metal and used to measure a characteristic of the bath, as with a temperature sensor and to obtain simultaneously a sample of the bath for subsequent analysis. It is routine in the practice of making and refining molten metals and alloys to measure specific characteristics of the molten metal, such as temperature, dissolved oxygen content, carbon content, etc. with separate measuring elements individually immersed into the molten metal bath during the melting period. It is also routine practice to obtain a sample of the molten metal during the melting period for chemical analysis at a later time. Such a sample is normally taken by either pouring a sample of the molten metal into an appropriate mold or by immersing an expendable immersion sampler into the molten metal bath. These immersion samplers are usually vented cavities which freeze a sample of the molten metal which flows in after a fusible cap covering the cavity has melted.
Immersion assemblies for molten metal have been constructed to utilize expendable immersion pyrometer elements for measuring and to also include a cavity for freezing a sample of the molten metal. The sample cavity in these prior art devices is constructed as part of the pyrometer element and is arranged to be insertable into a protective sleeve which normally protects the end of the lance used for manipulating the device into the molten metal bath. The sample cavity is oriented in line with the temperature measuring element. Access to the cavity is sometimes provided on the side of the sleeve and sometimes through the end of the sleeve through the same opening as that used by the temperature measuring element. In all of these prior art structures, the combination units are more complex than the standard sensors or samplers and therefore are expensive elements. Such special elements have a limited use in that their expense dictates that they not be used unless simultaneous measurement and sampling are needed. Thus, it is necessary to have available the standard expendable immersion pyrometer elements and standard sampling elements as well as the special dual purpose elements for economical operation during those times when a sample is not needed simultaneously with a measurement.
It is an object of this invention to provide a device for simultaneously making a measurement of a characteristic of a molten metal sample as well as for taking a sample of the bath.
It is also an object of this invention to provide a device for simultaneously measuring a characteristic of a molten metal bath and taking a sample of that bath using standard elements so that the expense of maintaining an inventory of special elements is minimized while providing the flexibility of separately making a measurement or taking a sample, or doing both simultaneously.